Winding mass

Abstract

The invention relates to a winding mass ( 10 ) for a watch movement, comprising a geometric rotation axis ( 100 ), a peripheral portion ( 10 ) and a connecting portion ( 13 ) between the peripheral portion ( 10 ) and the rotation axis ( 100 ), the density and the mass of the peripheral portion being greater than those of the connecting portion. The connecting portion ( 13 ) is moved by means of bird feather-like portions ( 20 ).

The invention claimed is: 
     
       1. A winding mass for a watch movement, comprising an axis of geometric rotation, a peripheral portion and a connecting portion between the peripheral portion and the axis of rotation, wherein the connecting portion is provided with bird feather portions, each feather portion being obtained by stamping a bird feather, each portion comprising a portion of the rachis of said bird feather, and barbs. 
     
     
       2. The winding mass as claimed in  claim 1 , said portion of the rachis is oriented radially between said axis of geometric rotation and said peripheral portion. 
     
     
       3. The winding mass as claimed in  claim 1 , said feather portion being in the shape of a feather. 
     
     
       4. The winding mass as claimed in  claim 1 , comprising two superposed levels of feathers. 
     
     
       5. The winding mass as claimed in  claim 1 , comprising rigid spokes between said axis of rotation and said peripheral portion, said spokes being at least partially covered by said feather portions. 
     
     
       6. The winding mass as claimed in  claim 5 , said spokes being made of metal. 
     
     
       7. The winding mass as claimed in  claim 5 , said spokes being made of sapphire. 
     
     
       8. The winding mass as claimed in  claim 5 , said spokes being radial. 
     
     
       9. The winding mass as claimed in  claim 5 , said spokes being of a color different than that of said feather portions. 
     
     
       10. The winding mass as claimed in  claim 5 , said feather portions being bonded to said spokes via the lower end of their rachis only. 
     
     
       11. The winding mass as claimed in  claim 5 , said feather portions being bonded to said spokes by the lower end of their rachis and by the upper end of their rachis. 
     
     
       12. A method of manufacturing the winding mass as claimed in  claim 1 , comprising the following steps:
 selecting feathers; 
 stamping a feather-shaped feather portion from the vane of each selected feather, each stamped portion comprising a portion of the rachis; 
 bonding the rachis of the stamped feather portions onto a winding mass oriented radially with the rachis close to the axis of geometric rotation. 
 
     
     
       13. The method of  claim 12 , comprising a step of chemically treating said feather portions. 
     
     
       14. The method as claimed in  claim 12 , said feathers being bonded by their rachis only.